The present invention is directed to a hub assembly, and more particularly, to a hub assembly for attaching a set of blades to a drive shaft.
Impellers are widely used as a component of an agitator assembly to mix various fluids.
An agitator assembly typically include a drive shaft with one or more impellers mounted to the drive shaft. Each impeller includes a plurality of blades of that are attached to one or more hubs, which are in turn coupled to the drive shaft. The blades of each impeller extend radially outwardly from the hub. Each hub and blade combination is located inside a vessel that is filled with a fluid to be mixed.
When an agitator assembly is used in sanitary applications, such as in the food, beverage or pharmaceutical industries, the vessels containing the fluids are closed. In order to install and service components of the agitator assembly, a manway (i.e. a sealable opening) is provided in the vessel. The manways are typically on the order of 24 inches in diameter, and many impellers are larger than the manway in the associated vessel. In these cases the impeller must disassembled such that each impeller component can fit through the manway. The impeller is then reassembled inside the vessel as it is attached to the drive shaft. In sanitary applications it is also desired to have an agitator assembly having relatively smooth outer surfaces with any voids, crevasses or dead spaces sealed from the fluid contents of the vessel.
The present invention is a sanitary hub assembly which can be easily attached to a drive shaft. In a preferred embodiment, the invention is an assembly for rotationally coupling a set of blades to a drive shaft. The assembly includes an upper locking hub rotationally coupled to the drive shaft, a lower locking hub rotationally coupled to the upper locking hub, and a lower ring located between the lower locking hub and the upper locking hub, the lower ring having a set of generally radially extending blades. The assembly further includes an upper ring located between the lower ring and the upper locking hub, the upper ring having a set of generally radially extending blades, wherein the upper and lower rings are rotationally coupled to the drive shaft.
Accordingly, it is an object of the present invention to provide a sanitary hub assembly which can be easily disassembled to fit through a manway and easily reassembled and attached to a drive shaft.